Parachute system



Aug. 9, 1949. P. FRIEDER ET AL 21,478,758

PARAGHUTE SYSTEM Filed June 21, 1947 8 Sheets-Sheet 1 FIG. 9.

INVENTORB LEONARD F i'-r/EDER I l 2N5? 5'. HNKEN Mar ATTORNEY 1 1949- L. P. FRIEDER ETAL 2,478,758

PARACHUTIE SYSTEM Filed June 21, 1947 8 Sheet s-Sheet 4 Wg TER 5f F7NKEN M1: 5. MM

ATTORNEY Aug. 9, 1949. I P. FRIEDER ET AL 2,478,758

PARACHUTE sis TEM Filed June 21, 1947 a Sheets-Sheet 7 INVENTORS BY WAL 75F? .51 F/NKE/v v ATTORNEY Patented Aug. 9, 1 949 Leonard P. Friedcr, Great Neck, and Walter S. Flnken, Brooklyn, 'N. Y.,""as'signor's, by direct and mesne assignm Finance Corporation ents, ito Reconstruction ern ieefiee ena 194, sr al li ita e 1 V This invention relates to parachutes and in one importantrespect, isdirected toprov-ision forltlieir release in a novel and sequential manneryafiiording parachute operation of an improved character and under conditions where it has not heretofore been deemed feasible.

This application .is a continuationin part of our copending application-Serial No; 669,814, filed May 1-5, 1946, now abandoned; for Parachutes, prosecution of said copending application having been terminated in-favo'r oftheipresent applica tion wherein the claims of said copen'ding application'have been continued.v

More particularly," (the invention relates to parachutes and parachute systems'for useu'nder any of a variety lof severe or unusual .circu'mstances when an aerially disposed .object is to be moderated in movernenwreferring for 'iexample to movement downwardunder-the influence of gravity, or to .other directions of motion and incipient motion Iwhere -braking'or retardation may be required. Thus one of many applications of the invention is in iretarding an'd flowering safely to earth, a high speed projectiletraveling atv'ery high altitudesuch as' a pilotless aircraft sent far aloft for-thelpu'rpose of meteorological, photographic or other observations. Other' applications are in vthe case ofloads, animate or 'inanimate, dischargedifrlom aircraft movingat excessive heights or at extraordinary speeds; and also exceptionally heavy loads, or those-for which some delayed retardation is desired or for which a specific directional stability sought. @These are merely some examples ;of the character of loads wherein the advantages of the invention are most significantly realized, and numerous other examples will doubtless become apparent, in View-of the-following disclosure of certain illustrative embodiments. It. will be understoodlthat references herein to a; loadl are intended, unless otherwise stated, to-meanany: aerially located or locatable object,.body or as sembl y to Which-the movement-moderating;action of, a parachute. to be applied. i

1 Important objects ,ofthe invention 7 are .to provide improved parachute operation under circumstances such,as,;,are mentioned above, and especial-1y where parachute equipmentof the sort generally available prior to our discoveries could not be emp1oyed;. at al1,,or at least with complete satisfaction. In one specific, aspect, the invention i olves, t m tic rel ase of: ra ute i r s in redeiermi ss sgea .1 eonditions, particularly forloads so situated that h r e1 ninetee ava lab e, i th vicinitv,

20 c i (Cl.,244;--138i the load, to take control; and thus a further obj ect to provide 'ii''wtindinore effective parachute relaslnsafl'angefi nts. 1

j parameunt rea ure of the" invention resides in" the shar ened;'seqiienti i' release of a plurality of parachutes, f0 esired retarding action'with a givfin load. A's 'was'disclosd alsoin our afores aidcopending application Serial No; 669,814; filed May 15, '1'946jforParachutesthere aremany circums'tanc'efs'wher'e' afisir'i'glecanopyje; g; of the usualtyperelase manuallyori'by a static line. cannot besafelyempioyes; for example when the load is dropped from an aircraittraveling at veryh ig'h" v'elocit'yftlie shock occasioned uponthe opening" of the'p'ar'ajchute may 'wellibe sufficient to destroy the latter or itolinjur'e the load. We

have found that this problemofln l e loadsiina'y be foverc'o'me by providing aseries of successively" opened-"parachutes;"suclr as one or meresman auxiliary canopies followed. by "a main or large parachute, whereby a progressive vretardationftakesplacs"and'ithere is no excessive load shock at anytime. As will become furth'er apparehtin'th present disclosurejthereare many eireumstanees under 'iwhich two or jlmorei para-' chutes maybe advantageously used; each connected fin sup-porting relation tofthe' load and effective 1 to the desii'd' extent Ifor' that purpose at least until'a succeeding canopy is' opened;

Further 'c'ibi'ects "of'th'e invention are to provide improvements in the retentiomrhousing .and'lrelease ofparjaichutes; especially for the realization of automatic releas'' 'andto permit a practical utilization of sequentially released. tparaichutes under" remote or'otherwise unattended control. {To these an'dfothef'ends, the" invention embraces novel arrangements andinstrumentalities, such as are exemplified" in the annexed drawings and thelfollowing description,,tvhiciiare believed to afiord an;ample,;il1ustrative zdisclosure of the broader, underlying principles. 2 7

- Referring totheidrawingsf 'Fig'.. 1, is a reduced; simplified view .of a pilotlesslaircr-aft .or eproiectile underl the retarding effect .of alsmalli parachute provided in'yac'ciordancelwith theinventionf" i Fig. 52, is ;a likejview jot-the same craft, .ShQWing thestructuree'just after a secondgparachute has beenreleased.an tisnpenine up;

-1 Fig. :3, is J alyfurthenyiew ;.ofj:the craft, showing both anopiesinful ,b .0c. ,n 1;

-.l i l sla. perspebtiye .view of, the; fuselage lei i theeraftew th-ncrtions,.hro e i away, show n he:parachute etaini estr etn e;' eEie-efi isl t-s d elevatig aeniar e .relative t 3 Fig. 4, of the parts indicated in the latter, with certain covering portions broken away;

Fig. 6 is a section on line 6--6 of Fig. 5, also illustrating the parachutes in packed condition;

Fig. 7 is a section on line '|'I of Fig. 5, showing certain control instrumentalities;

Fig. 8 is a detail view, chiefly in plan, of a timing device shown in Figs. and '7;

Fig. 8a is a fragmentary section on of Fig. 8;

Fig. 9 is a section corresponding to Fig. 6 but illustrating the parts just as the second parachute is being released;

Fig. 10 is a fragmentary elevation, taken from the interior of the compartment, to show parts associated with the outer door;

line 8 a8a Fig. 11 is a wiring diagram of apparatus used I with instrumentalities shown in'Figsfll and 10;

Fig. 12 is a sectional view similar to Fig. 7,- but showing a modified form of control;

Fig. 13 is a schematic view of another embodiment of the invention, showing a load under the retarding action of one of a series of parachutes to be released from structure there illustrated;

Fig. 14 shows diagrammatically the association of load and parachute pack, in this instance before the release of any parachute;

Fig. 15 is a schematic, perspective view, illustrating one manner in which the first parachute of Fig. 13 might be connected for release;

Fig. 16 illustrates an initial stage in the release and discharge of a second parachute in the device of Figs. 13 to 15;

Fig. 17 shows, somewhat diagrammatically, the relation of the several parachutes after all have been released in sequence but before the final one has fully opened;

Fig. 18 similarly illustrates the arrangement of parachutes after all have opened; and

Fig. 19 is a diagrammatic section illustrating a form of time delay device.

For the sake of illustration the apparatus of Figs. 1 to 11 inclusive is shown embodied with a jet-propelled pilotless aircraft 20 having a fuselage 2 I, wings 22, tail 23 and jet propulsion means 24 conveniently spaced from the parachute pack assembly which is described below. It may be assumed that this aircraft or projectile has traveled to an extremely high altitude, e. g., of the order of 50,000 feet and is progressing at a high velocity, for instance well in excess of 500 miles per hour. It may be further assumed that at a desired stage in the flight of the craft, as when its fuel is about to be exhausted or when it has reached a desired vertical or horizontal position, it should .be brought to earth with safety. For example the craft may carry observational equipment which, with its records, must be retrieved, or there may be any of a variety of other reasons for recovery of the projectile.

To that end, a multiple parachute pack is disposed beneath a door 26 (Fig. 4) which originally closes an opening 21 at an upwardly and sidewardly facing portion of the fuselage 2!, near the head of the craft. The pack contains a small parachute 30 having its load line 3! attached through a connector assembly 32 to a bridle 34 which may consist of a plurality of lines or cords secured to appropriately spaced positions on the fuselage 2i and extending to an apex at the connector 32, as shown. In further accordance with the invention, the small parachute is released at the desired time, for example in response to a radio signal from the ground or elsewhere'and when it opens, this canopy 30 is accompanied by no more load shock than can be properly handled, and yet it serves to retard the speed of the craft 20, e. g. as the latter begins its down-- ward travel. Although this reduction of speed is presumably inadequate to provide a safe landing, it is nevertheless sufficient to permit safe release of a large or main parachute 40 having a load line 4| conveniently connected with that of the small parachute 30, e. g. at the connector 32. Upon final opening of the main canopy. the parts assume the positions generally indicated in Fig. 3, wherein the aircraft 20 is effectively supported by the main parachute 40 while the supplemental parachute 30 remains spread, with its axis at an angle such as shown, and with the further advantageous effect of tending to head the craft 20 into the wind as it descends. If desired, the connector 32 may comprise means (not shown) for disconnecting the load when it strikes the ground.

Bearing in mind the extreme altitude at which the initial retardation may be effected, means are also provided whereby the release of the main parachute 40 is delayed until after the first parachute has functioned as such for an appreciable time; For instance, by permitting the load 26 to fall under the moderating influence of the small parachute 30 alone for a considerable period, the total time of descent is greatly reduced and there is much less tendency toward lateral drift than if the main parachute had been opened at once; in fact, the release of the latter can be advantageously postponed untilit is fully needed (say within a few thousand feet of the ground) for the desired, relatively gentle deposit of the load. For these or other purposes, a delayed control in sequential parachute release is distinctly beneficial, and in accordance with the present discoveries, the supplemental control of the second parachute (or in other cases several successive parachutes) may be effected in a variety of ways, all at least in part independent of the release and functioning of the preceding parachute; examples of instrumentalities operating in some of such ways are described below.

Referring now to the structure which carries the releasably packed parachutes, the fuselage 2| (Figs. 4, 5 and 6) encloses vertical and horizontal walls 45, 46 cooperating with the door 26 to provide a'quadrant-shaped compartment having end walls 48, 49. A removable partition 50 disposed in a generally curved and slopin position between the upper end of wall 45 and the outer end of wall 46 sub-divides the space into an outer parachute compartment 5! into which the supplemental parachute 30 is packed, as in a known and appropriate manner for appropriate spreading and functioning of the canopy when released, and an inner compartment 52 containing the main parachute 40 which is similarly packed to bloom properly upon ejection. The partition 50 at its lower end has a flange 54 removably seated beneath a flange 55 that extends along inside the lower edge of the opening 21, and the upper ed'g'e 56 of the partition 50 is similarly retained by one face 51 of a large wedge-shaped longitudinal notch in a rod or shaft 58 that extends lengthwise at the top of the opening 21. The rod 58 is appropriately journaled at 59, 60 in the walls 48, 49 and has an extended shaft portion 61 on the other side of the wall 48 for purposes described below.

The door 26 may simply comprise a curved devotes againstshoulders at the top and bottom and retained by a pair-of lugs 63 at one'end and a latch generally designated 64 at the other end (Fig.

The fuselage has an opening '66 through'which the bridle lines 34 extend, more'or less slack, to the connector 32 and thus to the load line 3| of the packed small parachute-3i]. A cor-respondingly appropriate opening 61 "isx'also provided for these lines in the end wall 49. Provision is likewise made for the load :lin'e 4| ot the main parachute to extend around the partition on from the connector 32 (packed with the :small parachute) to the compartment 52-'-for example by allowing space as shown :at '69 between the end of thepartition 50 and the endwall '49. For clarity of illustration Fig. '5 shows the :compart ment without the parachutes, except'to indicate such position of the load-line "4].

While a variety of signalor other conditionresponsive instrume'ntalities "such as barometric means, speed responsive means, or means controlled b proximity of the aircraft to other objects, may be employed'to 'efiectrele'ase of the first para-chute, the illustrated example shows a radio control foro'pehing the latch 64 of the door 26. Referring to Figsrlil and ll, the latch comprises a sliding bolt 'lll held, under the ten sion of a coil spring 10a Lin engagement with a keeper H on the inner vface ei the-door. The bolt carries a pin I2 sliding in a notch 13 at the end of one arm 14 ofa bell crank lever pivoted to the fuselage and having its other arm 75 pivoted to the plunger-type armature16of a solenoid 1?. Thus upon energi'zatio'n ot "the solenoid the are mature I6 is attracted downwards (in Fig. 10), rocking the lever I l- H3'aridslidi'zig the bolt 19 to the left so as to release the door.

By way of diagrammatic illustration ahd'having in mind that any of a varietyof radio or like controls may be provided for energization of'the described electromagnetic means, Fig. l1 shows, in highly simplified form, a-s'ystem comprising a radio receiver 89 feeding its signals through an amplifier 8! which isconnected to -energize a relay magnet 82, i. esotnat the'maenet is energized when the apparatus here illustrated (and carried elsewhere on the aircraft) receives a radio signal of desired character Upon energization of the relayrnagnet 82, the normally open relay contacts 83 are closed, energizing the solenoid l! in a circuit which extends rom contacts 33 through conductor 84, battery 85, conductors 86, 81 to the solenoid-and-back from the solenoid through conductor 89 t'o'the contacts 83.

Upon release ofthe-door 26, it springs out and falls clear of the aircraft; although supplemental resilient mean may be provided to'insure opening of the door, the packed par chute '3flwill'ordinarily have enough resilience for that purpose, at least to 'such' extent thatthe door may be caught by the passing stream of air and thereby have'itself and its lugs 33 pulled clear of the opening.

Thereupon the small parachute springs or fall from the com artments! and opens in its intended manner, having" pulled withlt its lead line 3! and the bridle 34. Thejcanop'y is thus deployed as shown in Fig. 1 and'the main 'parachute es remains locked'behindthe partition 50, with its load line section! I slack, as shown.

While any of a'variet or ineclianismsfor actuating the release rod'58 may be provided, one

simple and efiective arrangements shown for purposes of illustration in-Figs. 5. k8 enact; 'The shaft extension 6| I carries a 'cam-ilike element providing a radial shoulder *90 normally "engaged by a detent 92 which is centrally pivoted eit93- and pivotally connected at it other end we link' 94 to one arm of a lever 95. The lever 95 ispivotally fulcrunied to a support96, which may also cairy the pivot for the detent 92, and the outer end of the lever has a slot 98 whicliis' slidabiy-eneaeed-by an operating pin at or a rotary solenoid Hit. Although other electromagnetic means may be uses, the device 'lumwhicnmay beois known type. affords a relatively powerfuldis placement in response to energlza'tion, vial moa ing' the pin 99 in a clockwise direction-around-the center of the solenoid structure 'as seen in Fig; "7; A spring I 432 under tension maintains the as, sembly in the position shown until "the Sole-hold is energized. p

{The shaft portion 6| also carries a pin Hi3 which rests against a stationary stop lot, ,to prevent clockwise rotation of the "shaft as seen in Fig. '7 and thus to maintain the notched rod in its proper, normal'position of Fig. 6. A radial arm I66 on the shaft BI is connected by a tensioned spring I67 to a fixed locality of the su porting structure. It will nowbe seen that upon energization of the solenoid, the pin 99 is moved 7 (barometric) or speed-responsive or radio com trolled or radio echo' actuated or like instrumentalities may be employed to release the inner. parachute upon occurrence of such other-types of predetermined conditions, the present struc ture includes a timing device ill! for actuating the solenoid I08. Such device may bear a' su-i-table known character adapted to close a pair of contacts i ii after a redetermined. time-interval which may be initiated in any desired a manner, for instance by the release'ofthe small parachute 36. Thus the clock device Ho has a face i I4 with a setting hand H5 that can be turned, for example manually,"'to a selected position and there held so that upon release its: spring mechanism (not shown) will operate for a corresponding interval, moving the hand bac'kto zero position and there closing the contacts H2. To hold the hand I It in a selected position, there is provideda detent pin it I slidably extending; through a socket H8 at a selected portion of the.

face, the 'clockand pin socket having anappro pin I i I through the cover I20-and the corresponding aperture in an outer cover over-ithe controlcompartment. -'lhis action releases the hand H5, and triggers the clock mechanism so that after a predetermined number of seconds or other interval acontrol is 'e'ifectedas'by closure ofthe' Thus as 'the para-ev contacts I I2, to energize the' rotary solenoid I and release the main parachute 40.

The circuit for the solenoid I00 extends from the contacts H2, through conductor I21, a battery I28, conductor I29, through the solenoid and back through conductor I30 to the contacts.

Thus at the end of a predetermined time interval, which in this instance is initiated by the release of the small parachute 30, but is at the same time at least in part independently controlled (i. e. by the setting of the clock device N0), the main parachute 40 is released by unlatching its covering partition 50. If desired, a tensioned elastic cord I32 may be held in position such as shown in Fig. 6 beneath the large parachute, to facilitate ejection of the latter, release of the pressure on the cover 50 permitting the stretched cord I32 to contract as shown in Fig. 9, throwing the parachute clear for its deployment in a desired fashion. The partition 50 is ordinarily, in fact, thrown or swept clear of the aircraft at such time, thus further facilitating ejection of the large parachute.

In this fashion, the canopy 40 is thus permitted to expand as shown in Figs. 2 and 3, whereby the craft 20 is now in effect substantially entirely supported, through the tightened load line M, by this parachute. Thus, for instance, if the timing or other control of the latter has been such as to release it within appropriate distance of the ground, it performs its function for a short but effective time, bringing the craft safely to rest.

It may sometimes become desirable to eject the main parachute simultaneously with the auxiliary canopy 30 or in effect, without regard for the functioning of the latter. For example, observation from the ground may reveal that the craft 20 is in trouble at a low altitude or should be recovered under any other circumstances where the sequential parachute operation is either unnecessary or undesirable.

To meet such emergencies the apparatus includes a supplemental relay I40 having a contact arm I4I adapted to bridge and thus close a pair of contacts I42 connected in shunt with the clock-controlled contacts H2. Referring to Fig. 11, the armature of relay 82 may carry another pair of contacts I44, insulated from the contacts 83 and normally closed until the relay is energized. A supplemental radio circuit, for instance including the receiver I45 and cooperating amplifier I46 are provided to energize a relay magnet I41 and thereby close a pair of normally open relay contacts I48; the receiver I45 isinsensitive to the type of signal to which the receiver 80 responds. The contacts I48 are included in a circuit with a battery I50, that extends through the solenoid 11 and the normally closed contacts I44 of relay 82, and the winding of relay I40 is connected in shunt in the same circuit, 1. e. across the series connection of solenoid 11 and contacts I 44.

Thus upon receipt of a special signal which will affect receiver I45 but which, being on a different carrier frequency or otherwise of different character, will fail to actuate receiver 80, the relay magnet I41 is energized to close its contacts I48, and the contacts I44 remain closed. In consequence both the solenoid 11 and the relay magnet I40 are energized from the battery I50. Energization of the solenoid 11 opens the outer door 26 in the manner previously described, and closure of the contacts I42 by the relay I40 operates the rotary solenoid I00 and unlatches the inner partition 50, likewise as explained above. Thus in an' emergency 9. special signal may be'sent from the ground or from an attending plane or the like, and may be selectively received at the pilotless craxft, so as to release all of the parachutes, and particularly the major parachute at once. For instance if the craft 20 is observed to be falling 'or in trouble at a region of too low altitude to wait for the sequential operation of the two parachutes, the main parachute may be released and opened at once, for safe delivery of the load to the ground.

It will be noted thatthis supplemental or emergency control constitutes means responsive to a special signal or .other predetermined condition whereby the main parachute can in effect be immediately released, and likewise any unreleased para-chute of preceding situation in the sequence of such devices. For example if the emergency arises after the'supplemental parachute 30 has been discharged but before expiration of the time provided by thedevice IIO, the described control eifectuates release of the large parachute substantially at once..

As explained above, among various kinds of control devices that may be employed for parachute release, certain specific and notably useful types are set forth herein [for illustration, a further example being shown in Fig. 12. This apparatus includes, in lieu of the timing device of Fig. 7, an altitude-responsive instrumentality that comprises a barometric device generally designated I60. It will be understood that other parts of the equipment may be identical with those shown in Figs. 1 to 11, except for the timing device and its controls, and are therefore not shown again in connection with the embodiment of Fig. 12.

The barometric device I is disposed in the control instrument compartment and among various forms of such means that may be used, a convenient structure includes a pair of dished members I6I, I62 clamped together at their flange-like peripheries to hold between them a stiff, resiliently flexible diaphragm I64. The

Y member I6I is imperforate and thus with the diaphrag m I 64 consitutes a sealed chamber adapted toexpand or contract in response to changes of pressure communicated to the outer side of the diaphragm through openings I65 in the member I62. An operating rod I66 extends from the center of the diaphragm to engage one arm of a lever I01, the actual engagement of the rod I66 with the lever, for instance to move it inwardly, being adjustable by appropriate means such as the screw I60 traversing the outer wall I69 of a ring or the like, carried by the rod I66. The outer end of the lever I61 transmits displacements, by a link I10, to one arm of another lever HI, and the opposite end of the lever IN is disposed to engage a contact operating member I 12 and close a pair of normally open contacts I14 upon predetermined displacement of the linked assembly of levers.

The arrangement may include parts as shown in preceding figures for turning the shaft portion 6| to release the main parachute, such means including the rotary solenoid I00 to be energized from the battery I28. The contacts I14 are connected, as shown, in series with the solenoid across the battery so that closure of the contacts energizes the solenoid and through the further mechanism, identified as in Fig. 7, permits the partition '50 to open and release the main parachute. The supplemental or emergency relay i40 may also be included as in Fla. 7 and con- 9 t o l d a in la l to the am ur o to release the main parach to substantially at once n" e onse t a nredc eriuiseq emer e c Signal or other condition, Asin Fig. 7, the normally opened contacts 14'? of the supplemental relay we are connected in shunt with the principal control contacts (contacts I14) for the rotary solenoid.

In operation, the screw I68 or other adjusting means may be prelinj i a ri'ly set for expected meteorological conditions, so that when the pilot.- less aircraft or other load has descended to a pre-.- determined al'titude, thecorresponding inward displacement of the diaphragm I54 willrock' the levers it? and Ill sufilcientiy to close the contacts I14 and energize the relay Hill. I n this fashion, and assuming that the small or prelim? inary parachute has opened at the outset to provide its described retarding action, the main parachute is not opened until the load reaches a predetermined altitude, whereupon it is released and performs its intended function in bringing the load to the ultimately desired condition of descending travel. An arrangement of this sort is of special advantage for'loads falling from extraordinary heights, since the supplemental parachute (or parachutes, ii mor'e'than one such are employed) may be relied upon to sustain the load until it reaches a relatively low position, for in stance an altitude or several thousand ieet. Then the main parachute is automatically released and promptly moderates the descent of the load to the ultimately desired, terminal Velocity.

In this fashion the total time of iall is submumm shortened and the; tendency of the load to drift is very greatly reduced over a large portion of its downwardpath, i.'e. while the small parachute alone is in operation. Inconsequence there is an effective stabilization of the direction in which the load travelsor in other words, much greater accuracy may be obtained in depositing the load in a predetermined locality on the surface of the earth. If desired, a light spring I16 may be, associated withthe assembly of levers and linkage to hold the; parts in normal condition until positively displaced by movement, e.'.g'. to the 1 ft as'seen in E12. 1. 501! the diae phrag'm I 64.

By way of further example Figs. 13 to 13 inclusive illustrate another embodiment wherein a series of,'say, four parachutes are. to be released in desired sequence to control thedescent of a load diagrammatically represented at 280. Further by wayof example, it will be assumed that the load in this instance is to be discharged from ahigh altitude airplane or the like, so that the initial parachute of the sequence can be released under direct control on the plane, as by the usual static line.'

The parachutes are releasably packed and dis-.

posed in a series of compartments 2], 202, 203 and 204 andmay comprise any desired arrangement as to the relative size and ultimate disposition of their canopies, as by connection to a single or multiple load line arrangement for support of the load when released.

For instance compartments 20!, 282 and 2113 ma respectively contain "small "or supplemental parachutes 205 206' and 2E1 of increasing size, to be released in the stated order, and the compartment 204 may contain a'main parachute 238 for final release to provide the ultimate, principal support of the load-all in accordance with the principles hereinabove explained and also as described in our cited copending application Serial No, 669,814. Big. 14 shows the assembly of packed parachutes associated with the load, it being understood. that this. and other aspects of the drawings are purely diagrammatic and that the actual structure will depend on factors individual to use, including thenature of the load itself.

By way of further diagrammatic illustration, Fig. 15' shows the first compartment 2M, comprising a plurality of hinged or folding members 2m, 2!], ZIZ, which are adapted to open out as shown in Fig. 13 for release of the parachute and which are normally held together by suitable cords 215 engaged by a releasing device 216 having a removable pin'glfconnected by a cord 2 l8 and hook 219 to a line or other support are in the carrying plane, it will be understood that this diagrammatically represented structure may be of any type now employed for release of a single parachute by a static line, as by pulling a pin or the like from a releasing device'that retains the parachute; hence, structural details of such device are omitted from the present views.

The first parachute 2 05 has its individual load line 22 2 connected to a portion 223a of a main load line 223, the portion 223d being anchored to the load at 225. A supplemental cord 226 spliced to the line 222 carries a pin 22'! releasably retained by a timing device 228 associated with the second parachute container 252. It will be understood that this timing device, which may be constructed on known principles (and may indeed be essentially of the sort embodied in Figs. 1 to ll), is triggered by withdrawal of the pin 221, as irom an apertured arm 229, and after a desired period of time withdraws the arm so as to'open the compartment 2B2. For instance, a latch cord 21 fastened to the bottom 232 of the compartment may have a ring 233 looped over the arm 229, so that when the arm is withdrawn the ring is freed and the cover 235 of the compartment may open as shown in Fig. 16. The opening of the compartment when released by the latch may be efiected simply by the resilience of the packed parachute or by supplemental means such as a spring 236.

Thus upon release of the described latching parts for the compartment 2G2, the'se'cond parachute 266 is ejected, being retained by its own load line 237 which is connected. to a further portion 223!) oi the main load line previously described. As the second parachute 28$ moves, away from the opened compartment 2:12, it withdraws a pin 233 from a timing device 240, which may be arranged to control a releasable latch for the third compartment 203, in the same manner as described for the compartment 252. Thus upon the end of another predetermined time interval, the compartment 203 opens in the same manner as the compartment 202, to release theparachute 291. The latter is secured by its own load line 242. which connects with a further portion 2230 v of the main load line that extends beyond the connecting point of thelne 231 tor the preceding parachute.

open and the main parachute 29.8 is released, be-

ing secured to the further and final portion 223d of the main load line. If desired, release of the large parachute may be facilitated by a .pilot parachute 24B attached to its hem.. Likewise, some further control may be effected by the opening of one or another of the parachutes; for instance, if it is desired to initiate operation of meteorological equipment or the like (not shown) in the load 280 when the main parachute is being deployed, a lanyard 249 may be spliced to the load line section 223d so. that a pin 250 will be pulled from a suitable control device (for triggering such equipment) as the parachute is released.

It will now be appreciated that the arrangement of Figs. 13 to 18 constitutes provision for sequential release of a series of parachutes, in this instance each in a predetermined timed relation after the release of the preceding one, and after such preceding device has actually func tioned as a parachute for a desired time. Thus high altitude load or a rapidly traveling or other high-momentum load may .be retarded gradually until it reaches such condition of speed or altitude as is desired for operation of the main supporting parachute 288. To summarize the sequence of operations, the first parachute 205 is ejected by a static line or the like and at the outset forms the sole support for the load. After a certain time the second parachute 206 is released, and the two canopies then cooperate to constitute such support until the end of another time interval, when the third parachute 201 is released to contribute its supporting effect also, as shown in Fig. 17. After further predetermined delay the main parachute 208 is ejected and blooms-thereafter providing in the illustrated arrangement of Fig. 18, the principal. load-retarding action.

As each parachute previous to the main one is ejected, a still further portion of the main load line will extend, more or less slack, from the lower end of the individual line of the last ejected parachute back to the pack assembly. In some instances, to avoid fouling or the like, it may be desirable to tie such preliminarily doubled, slack part of the main load line to the extended part by light cord which will be readily broken by the tension of the succeeding parachute when it is deployed. Thus in Fig. 17 the load line portion 22311 is shown lightly tied to the junction of the load line portions 2230 and 223?), at t]. As the main parachute 208 blooms fully from the condition shown in Fig. 17 the light cord at 25! is broken, permitting the line section 223d to be pulled up to the position of Fig. 18.

It will be understood that because of limitation of space in the drawings, exact representation of the linear dimensions and proportions of the several load lines is not there attempted; but persons skilled in the art will readily understand that the several lengths of line are appropriately chosen to afford the desired ultimate arrangement, e. g. as diagrammatically shown in Fig. 18. It will therein be noted that the connections of the branch lines to the main load line assembly (223a to 223d) are spaced apart by distances at least as great as the over-all lengths of the branch lines and their attached parachutes; it being further noted that the main parachute load line 4| in Fig. 3 represents a similar spacing with respect to the auxiliary parachute 30 and its line means. v

For completeness of illustration, Fig. 19 shows one example of construction for timing devices such as may be used in the apparatus of Fig. 13, e. g. the timing device 228. In a suitable enclosure 255 a crosshead 256 on the arm 229 restrains a powerful, compressed, coil spring 258. The arm 229 also mounts a plunger 260 adapted to travel through a liquid-filled cylinder 26!, the plunger having a very small opening 262 so that it will provide a correspondingly slow dashpot action in the cylinder. When the pin 221 is pulled, the spring urges the assembly to the right, but the retarding effect of the dashpot arrangement provides the desired time delay, i. e. in reachin the end of the stroke, wherethe ring 233 is freed for release of the latch constituted by it.

An advantageous feature of the use of multiple parachutes, for instance as described herein, is the effect of the several canopies in operating with their axes tilted at angles (inversely determined by their diameters) to a true vertical line, or to the line of load descent. Thus for instance where there are only two parachutes they are displaced to opposite sides of a center line; where there are a number of small parachutes and a single main parachute, the small parachutes are all displaced on the same side of a vertical line, whereas the main parachute, balancing such displacement, needs to be tilted only slightly, and in fact inappreciably, in the opposite direction, as shown in Fig. 18, It will be understood that these advantageous effects of positional relationship of the deployed canopies are obtained with arrangements of two (Fig. 3) or more (Fig. 18) parachutes arranged and connected as shown in the drawings, whether the canopies are deployed at substantially delayed times or whether they are set free. together and simply deploy in sequence as their successively longer load line connections pay out and tauten.

It may be further explained that these effects are the result of several forces'of reaction, 1. e. exerted by the parachutes, acting on a common load or weight along the stress lines that adopt angles such as shown inFigs. l'land 18. For example, the several auxiliary parachutes 205, 206, 201 (and indeed also the main parachute 2H8) produce reactionary forces on the load 200 in magnitudes substantially proportional to the square of their diameters. The force of gravity on the load is perpendicular and constant along a given axis. When this weight is acted upon by two or more forces of reaction, e. g. by the auxiliary parachutes, the line of free descent of the weight may be considered to shiftilaterally to a new position parallel to the original perpendicular movement. This lateral displacement, correlated with the extent of the work lines from the apex of the parachute shrouds to their anchorages, causes the several work or load lines to be disposed at angles to the perpendicular, whereby full inflation of each auxiliary parachute is achieved without hindrance from their common connecting line .or other common connection. It may also benoted that the embodiment of truly hemispherical canopies in a multiple parachute arrangement according to the present invention provides a descent of more stable character than might be the case when other shapes of parachute, e. g. parabolic, are employed. It is believed that upon deployment of a second or further parachute in a series of them under the conditions described above, each hemispherical canopy will revolve on an equatorial axis, always exposing an inner surface of uniform radius to the air pressure, but with the air pressure diminishing on one side of the vertical axis while remaining constant on the other side. Under similar circumstances a canopy of parabolic form, for example, presents a non-uniform inner surface relation, with the tendency of causing the wind to emac atespill and of causing other improper: fim'ctioning otthe canopy.

Referringior instance,- to Fig. 17 itwillbe-understood that when the first canopy 2-fl5-.isopened, and. before any othersv arev released, its: axis is trulyvertical. so as'to support theloadinthe ordinary manner. Whensucceeding canopies are released, their inflation successively; relieves a pro.- portion of stress being carried by the previously deployed canopy or canopies; The proportion.- ing of. the load between or among the canopies causes each torotate on its. equatorial axis, so as: to diminish the cross-sectional area. represented by a vertical projection of. the canopy, without decreasing the: internal hemispherical area As a result the vertical line 210 or 2' representing the center of DIBSSLIIG-Ofthe vertical air stream moves correspondingly to one. side or other of the center line 212 or 214 of: the parachute; It willbeunderstood that a like displacement occurs in the case of a larger parachute following. smaller ones, although it may not beof.

sufliciently appreciable extent for illustration in a drawing such as Fig. '17-reference being made, for instance, to the canopy 207' when only the three canopies 2-05, 265 and 261 have. been deploy'ed. In all these respects, the directions of the canopy center lines are controlled by the physical laws of forcerelationships and for computation purposes, are susceptible of representation' by parallelograms of forces.

When. the equator of a hemispherical canopy is thus tilted. from; the horizontal with the parachute moving in perpendicular descent the: inner surface of the canopy is subject. to unequal pressures relative to the true center line 212 or 214 of the parachute. As a result each canopy will be" forced to move in the direction of greater pressure, e. g. the parachutes 205, 2% thus tending to move away from each other in the arrangement shown. The magnitude of this displacement is approximately governed by the sine of the angle formed by the intersection of the true center line (2.12 or 214+),with the center line of the vertical air currents (-210 or 2.1 l Thus as previouslyexplained, when the load 28:) is suspendedbetween the shroud apex of one parachute and that of the other (if there are only two canopies), the parachutes will tiltin opposite directions and; their load. lines will be spread apart at corresponding angles of tilt. As also generally explainedhereinabove, similar phenomena characterize arrangements of several'canopies of the, sort here disclosed.- In this manner the several parachutes automatically remain clear of the common or main load. line, and there is no fouling of one canopy by another as they are releasedin sequence, nor any such fouling or blanketing during subsequent flight or descent. a r

In practice these systems of plural canopies may likewise be of advantage, under at least certain wind conditions, to permit or facilitate the landing of the load in a definite position relative to the wind direction. For example, if the horizontal wind velocity is greater than the descending velocity, and also in some cases (e. g. of long distances of descent) where the horizontal wind velocity is somewhat less, the small or auxiliary parachutes will all fly with the wind, 1. e. be positioned to leeward, so that the'load will tend to land with a predetermined heading into the wind. For the last mentioned purpose, it will be understood that theload should be suitably connected, e. g. to prevent or impede its turning about a vertical axis relative to the angular position of the parachutes; about: such; axis; As stated above; it- 182 believed that; in these and: various" other respects. distinctly preferred, results: are obtained when: theinvention is embodied. with parachutes having hemispherical canopies;

It will. now be seen that the presentinvention affords improved parachute arrangements, which are of special utility under a wide variety of cir-- cumstances. and. which involve a novel. and sequential release of. the parachutes. The control may-be. automatic to whatever extent is desired andmay be; effected in a variety of ways and in response-to the occurrenceof a, variety of conditions, e.- g; the passage of time, the receipt of'apredetermined signal, the existence of a mode termined physical circumstancing of the load, or the. like. I

It is to be understood that. the invention is not limited. to: the. specific embodiments hereinv shown and described but may be carried out in other ways withoutdeparture from its spirit as defined by the following; claims.

We claim:

1. Parachute apparatus comprising, in com- 1 bination, a plurality of releasably packed parse chute assemblies to be associated with a load for sequential release oi theparachutes, each of'said parachute assemblies comprising a canopy and. load-supporting. line means which include shroud means beneath the. canopy and which extend from the canopy towardthe load, meansior con.- ncctin-gthe lower ends of the, load supportingline meansof. the parachute assemblies to av coinmorn unitary load and indirect supporting relati'onof each parachute assembly therewith, a first parachute assembly and. an immediately SllhSBa quent parachute assembly, of said sequence, beingreleasable to deploy at successively more re mote localities from the load, the line means of said subsequent parachute assembly comprising a load linewhich extends from, its shroud means to the'lower end of said line means, said load line.

being longer than the aforesaid line means. of said first parachute assembly, said first parachute assembly being disposedv wholly at one side of and free of the said subsequent, parachute assembly at all localities above said connecting means when said parachutes are released, and means for releasing said parachutes in desired sequence, including means responsiveto occurrence of a predetermined condition at a determinable time subsequent to deployment of said first parachute, for releasing said subsequent parachute.

2. Parachute apparatus as described in claim 1, wherein. the last-mentioned means comprises a timing device controlled by a previous parachute inaccordance with release thereof, for releasingsaid subsequent parachute in response to occurrence of. a predetermined period of delay.

3. Parachute: apparatus as described, in claim 1, wherein the last-mentioned-means comprises an altitude-responsive, device for releasing said subsequent parachute at a predetermined positional conditionof the load.

4. Parachute apparatus as described in claim 1, wherein the parachute releasing means includes means responsive to a predetermined signal traveling thereto from a locality remotely and aerially spaced from the load, for releasing the first parachute.

5. Parachute apparatus as described in claim 1, wherein the last mentioned meansis adapted to be delayed in its operation for releasin said subsequent parachute, until after a preceding parachute of the sequence has been released and has functioned as a parachute for at leastian appreciable time, and wherein the releasing means also includes emergency means responsive at any time to another predetermined condition for immediately and substantially simultaneously releasing said subsequent parachute and any unreleased parachute of preceding situation in the sequence.

- 6. Parachute apparatus as described in claim 1,

wherein the parachute releasing means includes means responsive to a predetermined signal of radiant energy, for releasing said first parachute and also includes emergency means responsive atany time to another predetermined signal of radiant energy, for immediately and substantially: simultaneously releasing said subsequent parachute and any unreleased parachute of preceding situation in the sequence. '7. Parachute apparatus for moderating the movement of a load to reach a predetermined ultimate condition of descending travel, comprising, in combination, a plurality of releasably packed and sequentially releasable parachutes adapted for association together with a load for support thereof when released, a first one of said parachutes having a minor retarding effect and a subsequent one of said parachutes having movement-retarding effect substantially greater than the first and sufiicient to provide said predetermined ultimate condition, means for releasing said parachutes in desired sequence, including means responsive to occurrence of a predetermined condition for releasing said subsequent parachute, compartment structure for holding the parachutes and having an opening through which the parachutes are to be released, and a movable partition separating an inner chamber of said compartment from said opening and having a releasable fastening, said first parachute being disposed on the outer side of said partition and said subsequent parachute being disposed in said inner chamber, and said condition-responsive means comprising means for releasing the fastening of said partition.

' 8. Parachute apparatus comprising, in combination, a first parachute assembly comprising a canopy and load-supporting line means including shroud means extending from the canopy to a point beneath it and a load line extending down from said point toward the load, a second parachute assembly comprising a canopy and loadsupporting line means which include shroud means beneath the canopy and which extend down from the canopy toward the load, and means for connecting the lower end of the load line of the first parachute assembly and the-lower end of the load-supporting line means of the second parachute assembly to a common, unitary load and in direct supporting relation of each parachute assembly therewith, said load line of the first parachute assembly being longer than the load-supporting line means of the second parachute assembly so that said first canopy and its shroud means may deploy above the second canopy, and said second parachute assembly being disposed wholly at one side of and free of the first parachute assembly at all localities above ihe aforesaid connecting means, so that each parachute assembly may deploy separately from and clear of the other and in direct supporting relation to the load.

9. Parachute apparatus comprising, in combination, a first parachute assembly comprising a hemispherical canopy and load-supporting line means including shroud means extending from the canopy to a point beneath it and a load line extending down from said point toward the load, a second parachute assembly comprising a hernispherical canopy and load-supporting line means which include shroud means beneath the canopy and which extend down from the canopy toward the load, and means for connecting the lower end of the load line of the first parachute assembly and the lower end of the load-supporting line means of the second parachute assembly to a common, unitary load and in direct supporting relation of each parachute assembly therewith, said load line of the first parachute assembly bein longer than the load-supporting line means of the second parachute assembly so that said first canopy and its shroud means may deploy above the second canopy, and said second parachute assembly being disposed wholly at one side of and free of the first parachute assembly at all localities above the aforesaid connecting means, so that each parachute assembly may deploy separately from and clear of the other and*in direct supporting relation to the load.

10. An apparatus of the character described comprising a main parachute, a load line connecting the load to said main parachute, a plurality of branch lines extending from said load line, a secondary parachute on the end of each of said branch lines, said branch lines bein spaced apart along the load line by distances greater than the lengths of the branch lines and said secondary parachutes being graduated in size to decelerate the load before the main parachute is fully de ployed. Y

11. An apparatus of the character describe comprising a main parachute, a load line connecting the load to said main parachute, a plurality of branch lines extending from said load line, a secondary parachute on the end of each of said branch lines, said branch lines bein spaced apart along the load line by distances greater than the lengths of the branch lines and said secondary parachutes being graduated in size to decelerate the load before the main parachute is fully deplayed, each of said main and secondary parachutes having a hemispherical canopy.

' 12. An apparatus of the character described comprising a load line attached at one end to the load, a plurality of branch lines extending from the load line and spaced apart distances at least as great as the lengths of the branch line, a parachute attached to the end of each branch line and another parachute attached to the end of the load line, the parachute nearest the load being the smallest and the parachute on the end of the load line being the largest of the plurality of parachutes.

13. An apparatus of the character described comprising a main parachute, a smaller parachute, a long line connecting the main parachute to the load, and a shorter line connecting the smaller parachute to the load whereby when the main parachute and the load are launched at substantially the same time the smaller parachute will decelerate the load before the long line is tensioned to transfer control of the load to the main parachute, said main parachute having a canopy and shroud means therefor converging to a point under the canopy, said shroud means being attached at said point to said long line, said smaller parachute comprising a canopy and shroud means therefor, the aforesaid point being disposed at a distance from the load on said long line which is greater than the over-all length between the smaller parachute canopy agrariaand the load, measured along the assembly constitutedby saidsmallerparachute and the shorter line, and said smaller parachute, canopy and shroud means being disposed at one side of the long line so that said" smaller canopy and its shroud means may deploy clear of the long line atone side thereof. I

1.4. An, apparatus of the character described comprising .a main parachut e,,,a smaller. parachute, a long line connecting the main parachute to the load; and a shorter line connecting {the smaller parachute to theflQad, said mainjparachute having 'a canopy and shroud meansfltherefor converging to a point under the canopy, said shroud means being attached at said point to said long ,line, said smaller parachute comprising a canopy and. shroud meansttherefor, theaforesaid point being disposed ata distance from the load on said long line which is greaterthan' the over-all length between the smaller parachute canopyand the load, measured alongthe-assembly constituted by said smaller parachute and-theshorter line, and said smaller parachute canopy and its shroud means being disposed at one side of the long line so that said smaller canopy and its shroud means may deploy clear of the long line at one side thereof, said parachutes and lines being releasably packed, means for releasing the smaller parachute, and means for releasing the main parachute at a determinable time after the smaller parachute has been released, said last mentioned means including a control device therefor, controllable independently of the release of said smaller parachute, for determining said time.

15. An apparatus of the character described comprising a main parachute, a smaller parachute, a long line connecting the main parachute to the load, and a shorter line connecting the smaller parachute to the load, said main parachute having a hemispherical canopy and shroud means therefor converging to a point under the canopy, said shroud means being attached at said point to said long line, said smaller parachute comprising a hemispherical canopy and shroud means therefor, the aforesaid point being disposed at a distance from the load on said long line which is greater than the over-all length between the smaller parachute canopy and the load, measured along the assembly constituted by said smaller parachute and the shorter line, and said smaller parachute canopy and its shroud'means being disposed at one side of the long line so that said smaller canopy and its shroud means may deploy clear of the long line at one side thereof.

16. An apparatus of the character described comprising a main parachute having a canopy and including shroud lines therefor converging to an apex below the canopy, a load line connecting the load to said main parachute, said load line extending to the load from the said apex of the shroud lines of the main parachute, a branch line extending from a point on the load line, and a parachute smaller than the main parachute .on the end of said branch, said load line having a length between said point and the aforesaid apex greater than the over-all length of the assembly constituted by the branch line and its attached smaller parachute, and said last-mentioned assembly being disposed wholly at one side of and free of the load line at all localities above said point.

17. Parachute apparatus comprising, in combination, a releasably packed main parachute having a canopy and including shroud lines therefree-pf. th load :line at all localities above, said point. when .said parachutes rare :released, and meansiforasequentiall-y releasing the parachutes, includingmeanszforreleasing the mainparachute ata determinable time after the smaller para-v chute :has been :released, saidlast mentioned means .mcludinga control device therefor, 0 trollablerindependently .oI-the release-of said main parachute, for determining said time.

I8: Parachute apparatus comprising, in combination,.amainizparaichute having a py and including shroud lines therefor converging to an apex below the canopy, a load line connecting the load to said main parachute, said load line extending to the load from the said apex of the shroud lines of the main parachute, a branch line extending from a point on the load line, and a sec- .ondary parachute on the end of said branch, said load line having a length between said point and the aforesaid apex greater than the over-all length of the assembly constituted by the branch line and its attached secondary parachute, and said last-mentioned assembly being disposed wholly at one side of and free of the load line at all localities above said point when said parachutes are released, said parachutes and lines being releasably packed, and means for releasing said secondary and main parachutes in sequence, including a timing device controlled by the secondary parachute and set in operation by release thereof, and means controlled by the timing device to release the main parachute upon lapse of a predetermined time following release of said secondary parachute.

19. Parachute apparatus comprising, in combination, a main parachute having a canopy and including shroud lines therefor converging to an apex below the canopy, a load line connecting the load to said main parachute, said load line extending to the load from the said apex of the shroud lines of the main parachute, a branch line extending from a point on the load line, and a secondary parachute on the end of said branch, said load line having a length between said point and the aforesaid apex greater than the over-all length of the assembly constituted by the branch line and its attached secondary parachute, and said lastmentioned assembly being disposed wholly at one side of and free of the load line at all localities above said point when said parachutes are released, said parachutes and lines being releasably packed, and releasing devices for the parachutes and control means responsive to change in altitude of the load, for operating the releasing device of the main parachute, after the secondary parachute has been released.

20. A parachute apparatus comprising a' load line having the load attached to one of its ends and a main parachute attached to the other end, and a secondary parachute connected to the load line at a point intermediate the load and the main parachute, the apparatus being operated by 19 launching the load and thereby rendering the secondary parachute effective to retard the load before the main parachute opens, said parachutes and load'line being connected and arranged with the load so that only after the secondary parachute has" deployed and while it is acting in supportin'g-relation'to the load,the main parachute then deploys under the tension of the load on the load lineand above the secondary parachute, each of said parachutes comprising a canopy and shroud line'scon'ver'ging beneath the canopy, the

end of the'load line which is attached to the main parachute being connected to the lower end of the shroud lines thereof, the said load line having a length between its said last-mentioned end and the aforesaid intermediate point, which is greater than theover-all length between the top of the canopy of the secondary parachute and the said intermediate point, and the said secondary parachutehaving its canopy and shroud lines disposed wholly at one side of and free of the said load line.

LEONARD P. FRIEDER.

WALTER S. FINKEN.

20 REFERENCES CITED lhe following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,709,264 Holt Apr. 16, 1929 1,843,597 Coflman Feb. 2, 1932 1,938,853 Miller Dec. 12, 1933 2,326,813 Wilson Aug. 17, 1943 2,352,308 Bailey June 27, 1944 2,392,448 Atherton Jan. 8, 1946 2,405,333 Sheridan Aug. 6, 1946 FOREIGN PATENTS Number Country Date 129,329 Great Britain July 17, 1919 442,978 France July 3, 1912 OTHER REFERENCES Ser. No. 390,181, Hehs (A. P. C.), pub. May 25, 1943. 

